Headless chat SDK · TypeScript

Build the chat experience. We'll handle the wiring.

Framework-neutral runtime for streaming, tools, auth, transport, and typed message parts — designed so your team owns every pixel while agents and developers build against the same contracts.

5-minute quickstart →Read the product guide

hello.ts

$pnpm add ./gecx-chat-0.1.0-prototype.tgz

+ gecx-chat 0.1.0-prototype · 19 public exports

import { createChatClient } from 'gecx-chat';

import { createMockTransport } from 'gecx-chat/testing';

const client = createChatClient({

transport: createMockTransport(),

});

// → streams, tools, auth — no backend yet

Install in your project

Prototype tarball · zero credentials

curl -L -O https://gecx-sdk-portal.vercel.app/downloads/gecx-chat-0.1.0-prototype.tgz

pnpm add ./gecx-chat-0.1.0-prototype.tgz

The tarball is npm-format and works with pnpm, npm, yarn, or bun. Download gecx-chat-0.1.0-prototype.tgz.

Send your first message

Mock transport · No server

import { createChatClient } from 'gecx-chat';
import { createMockTransport } from 'gecx-chat/testing';

const client = createChatClient({
  transport: createMockTransport(),
});

const session = await client.createSession();
const { messages } = await session.send('Hello!');
console.log(messages);

The mental model

Concepts worth ten minutes

Skim these before writing custom transports, tools, renderers, or agent workflows.

All docs →

Concept

Sessions & Lifecycle

concepts / sessions and lifecycle

Concept

Task-oriented walkthroughs

Practical paths for the flows teams ask for first: React UI, tools, A2UI, and governance.

Guide

Data Governance

docs/guides/data-governance.md

Machine-readable contracts

JSON Schemas

Hand these 21 JSON Schemas to AI coding agents, validators, or contract tests when you need the public surface to stay precise.

Drop-in modules

Recipes

Pre-built components and integrations you can copy into your project with pnpm exec gecx add <id>.

registry.json →

Streaming indicators

Typing, progress, and stop affordances for streaming chat.

pnpm exec gecx add streaming-indicators

Tool call cards

Inline status cards for tool execution and approval states.

pnpm exec gecx add tool-call-cards

rich content

Citation previews

Accessible citation preview renderer.

pnpm exec gecx add citation-previews

rich content

Product carousel

Swipe-friendly product carousel renderer for commerce chats.

pnpm exec gecx add product-carousel

Suggestion chips

Tappable follow-up suggestion chips.

pnpm exec gecx add suggestion-chips

behavior

Accessibility controls

Focus return, reduced-motion, and keyboard control helpers.

pnpm exec gecx add accessibility-controls

For AI coding agents

One paste, and your agent is up to speed.

The portal serves llms.txt (short summary) and llms-full.txt (complete context bundle) tailored for Claude Code, Codex, Cursor, and Antigravity. Pair them with the JSON Schemas and the SDK tarball so an agent can build a mock-first integration without guessing at the API.

Agent setup guide →Download llms-full.txt

Read these first: <PORTAL>/assets/agent/llms-full.txt <PORTAL>/assets/schemas/messages.schema.json <PORTAL>/assets/schemas/tools.schema.json Install: pnpm add ./gecx-chat-*.tgz Goal: <describe what you want me to build>

Build the chat experience. We'll handle the wiring.

Install in your project

Send your first message

Concepts worth ten minutes

Architecture

Messages & Parts

Sessions & Lifecycle

Transports

Auth & Security

Permissions

Voice and multimodal

Agent Graphs

A2UI Catalog

Task-oriented walkthroughs

Vibe Coding Guide

React Integration

Client Tools

Server Tools

Generative UI (A2UI)